1. Field of Invention
This invention relates generally to surgical access devices, and more specifically to access devices adapted for use in minimal invasive surgery to provide sealed instrument access across a body wall and into a body cavity.
2. Discussion of Related Art
Surgical access to a body cavity, such as the abdominal cavity, is referred to as “open laparotomy” or “closed laparoscopy.” An open procedure involves an incision of sufficient size to allow a surgeon to place hands and instruments within the surgical site. In addition, the site must be open enough for the surgeon to clearly see what he or she is doing. There is often a need for multiple retractors, clamps, and sponges. All of these devices compete for room within the surgical site.
Laparoscopic or closed surgery eliminates many of the issues surrounding open laparotomy. In a typical pressurized laparoscopy, the abdominal wall is punctured and at least one trocar is inserted into the peritoneum. Gas is introduced into the abdominal cavity and to elevate the abdominal wall away from the internal organs. This results in a large, clear operating field. Additional trocars can be inserted as needed for various procedures. A laparoscope is used to provide visualization of the surgical site. The instrumentation for laparoscopic procedures has developed prolifically in recent years and the surgeons have become comfortable with a “remote-control” approach to various aspects of surgery. Cutting, dissecting, cauterizing, stapling and suturing have all been addressed by laparoscopic device manufacturers.
Despite the many advantages of laparoscopic surgery, there remain a few complex procedures that make laparoscopy difficult or risky. In some of these cases, a hybrid procedure makes the most sense. If one could have the visibility and open field of a laparoscopic procedure and the control of an open procedure, one would truly have it all. However, the two modalities tend to obviate each other. Indeed, there are some who would argue that the advances of laparoscopy would be in vane if an open procedure were added as a default.
In recent years, a few enterprising surgeons have advanced a method that they call “hand-assisted” laparoscopy or “handoscopy.” This involves placing one of the surgeon's hands inside the patient through an enlarged incision, while under laparoscopic visualization. With no protruding instrumentation normally used in closed laparoscopy, it is not required to perform overly challenging maneuvers
The challenge now facing the surgeon in this procedure is providing an adequate sealing means within the enlarged incision. The surgeon's hand must be comfortable, properly placed and free to move with a normal range of motion. In addition, the surgeon should be able to remove and replace his/her hand into the abdominal cavity without loss of pneumoperitoneum.
Several devices have been proposed in an attempt to satisfy the requirements of the “handoscopist.” They generally involve an elastomeric seal that fits through an incision and is held in place by retention means on either or both sides of the abdominal wall. The devices are generally complex and require several steps to place. One of the devices requires an adhesive to be placed on the exterior abdominal wall (skin) as the seal is adhered to the skin. This requires not only application of the adhesive but also a drying time. Allergic reactions and other complications must be considered when using this product. Another device makes use of a “toroidal balloon” that inflates to position the device and seal the incision. The surgeon must overcome the friction and sealing pressure of this device when inserting and withdrawing his/her hand from the surgical site. A further device involves the use of a built-in glove or sleeve. This arrangement diminishes the range of motion and the tactile sensation of the hand.
U.S. Pat. No. 5,848,992 discloses a surgical access device that allows the conversion of an open procedure to a laparoscopic procedure. In addition, the '992 patent discloses the use of such a device in a case where a large organ is to be removed. In this instance, an incision of adequate size is made initially and sealed with the device at the same time the trocars are being inserted
Notwithstanding these proposed devices, there remains a continuing need for a surgical access device that provides a flexible, simple and complete seal within an incision of adequate size for introduction of a human hand.